The objective of this research is to ascertain the regulation of villous motility and its role in gastrointestinal functions. It is proposed to continue the research on the isolation of villikinin and to gain more information on antivillikinin, especially its physiological role. It is of prime importance that villikinin be isolated and synthesized so that the action of pure villikinin can be investigated on different gastrointestinal functions. The methods used in this project are partially biochemical, for the isolative work, and partially physiological, for determining physiological function. The biochemical work includes ion exchange resins, column chromatography, droplet countercurrent chromatography, gas chromatography, etc. The physiological aspect includes observing villous motility on an exteriorized canine jejunal mucosal surface through a stereomicroscope, cannulation of the thoracic lymph duct in dogs for lymph flow determinations, isolation of biliary and pancreatic ducts for secretory activity evaluations.